1. Field of the Invention
The present invention relates to an apparatus for polishing the substrate of a hard disk used in electronic equipment such as computers.
2. Description of the Prior Art
In recent years, with the increasing tendency to use a hard disk drives as an auxiliary storage for electronic devices such as computers, the demand to be able to produce hard disk drives quickly and economically has increased. As is well known, the substrate of a hard disk (hereinafter occasionally referred to, for brevity, as "substrate") must be polished before a magnetic material can be coated on the opposite sides thereof.
In a substrate polishing machine used heretofore, a single substrate is fed into a polishing station and both faces or sides are polished at the same time. Following this operation the polished substrate is removed from the polishing station, and the next substrate is fed thereinto. However, as the substrates are polished one by one, the prior polishing process tends to be slow and time-consuming.
Furthermore, the prior substrate polishing machine is constructed to support the substrate in a horizontal position and polish the faces from above and below. This tend to induce the problem that the upper and lower surface of the substrate are not polished evenly.